When performing cuts with blades, saws, or other surgical instruments during surgical interventions, surgeons typically have good control of the surgical instrument with regard to direction and depth of tissue penetration. However, sometimes a surgical instrument may slip, be deflected, or stray from its intended cutting path. When a surgical instrument strays from its indented cutting path, it may inadvertently injure or cut other tissues.
For example, in knee arthroplasty, a surgeon may intend to preserve one or more tibial spines. When performing a horizontal tibial cut, the surgeon typically guides the blade in an anteroposterior direction. The surgeon guides the blade path so as to stay clear of the tibial spines. However, if the surgeon accidentally misdirects the instrument or if the instrument is deflected from its intended path, the blade path may extend into the tibial spines or other local tissues. This unintended cut of the tibial spines may result in the loss of ligament stability.
Deviation of the surgical instrument from its intended cutting path may also have harmful effects when performing surgical interventions in other parts of the body. For example, in the spine, deviation of a surgical instrument may result in neural damage or damage to bony or disc structures. In the hip, deviation of an instrument from the cutting path may potentially result in neurovascular damage or damage to bony and ligamentous structures. In a shoulder, deviation of the instrument path may potentially result in neurovascular or muscular damage.
Deviation from the cutting path may also lead to other unintended consequences. For example, failure to follow a cutting path may later result in misalignment or poor positioning of an implant. A poor fit for an implant may result in complete failure of the implant or other complications.